The Klout Score measures influence on a scale of 1 to 100, with 100 being the most influential. Klout uses data from social networks in order to measure:
How many people you influence; (True Reach)
How much you influence them; and (Amplification)
How influential they are (Network Score)
The Klout Score measures your influence online based on data from Twitter, Facebook, LinkedIn, Foursquare, YouTube, and more networks to come. Our philosophy is that influence is the ability to drive action so we focus on tangible indicators of influence like @mentions, retweets, likes, and comments. Your influence is relative; the Klout score takes into account how your level of influences compares with the rest of the Klout user population.